Newcomer Benjamin W, Neill John D, Galik Patricia K, Riddell Kay P, Zhang Yijing, Passler Thomas, Velayudhan Binu T, Walz Paul H
Am J Vet Res. 2017 Feb;78(2):239-243. doi: 10.2460/ajvr.78.2.239.
OBJECTIVE To determine titers of serum antibodies against 3 genotypes of bovine parainfluenza 3 virus (BPI3V) in unvaccinated ungulates in Alabama. ANIMALS 62 cattle, goats, and New World camelids from 5 distinct herds and 21 captured white-tailed deer. PROCEDURES Serum samples were obtained from all animals for determination of anti-BPI3V antibody titers, which were measured by virus neutralization assays that used indicator (reference) viruses from each of the 3 BPI3V genotypes (BPI3V-A, BPI3V-B, and BPI3V-C). The reference strains were recent clinical isolates from US cattle. Each sample was assayed in triplicate for each genotype. Animals with a mean antibody titer ≤ 2 for a particular genotype were considered seronegative for that genotype. RESULTS Animals seropositive for antibodies against BPI3V were identified in 2 of 3 groups of cattle and the group of New World camelids. The geometric mean antibody titer against BPI3V-B was significantly greater than that for BPI3V-A and BPI3V-C in all 3 groups. All goats, captive white-tailed deer, and cattle in the third cattle group were seronegative for all 3 genotypes of the virus. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that BPI3V-A may no longer be the predominant genotype circulating among ungulates in Alabama. This may be clinically relevant because BPI3V is frequently involved in the pathogenesis of bovine respiratory disease complex, current vaccines contain antigens against BPI3V-A only, and the extent of cross-protection among antibodies against the various BPI3V genotypes is unknown.
目的 测定阿拉巴马州未接种疫苗的有蹄类动物血清中抗3种基因型牛副流感3病毒（BPI3V）抗体的效价。
动物 来自5个不同畜群的62头牛、山羊和新大陆骆驼科动物以及21只捕获的白尾鹿。
方法 采集所有动物的血清样本，通过病毒中和试验测定抗BPI3V抗体效价，该试验使用3种BPI3V基因型（BPI3V - A、BPI3V - B和BPI3V - C）各自的指示（参考）病毒。参考毒株为近期来自美国牛群的临床分离株。每个样本针对每种基因型进行3次重复检测。对于某一特定基因型，平均抗体效价≤2的动物被视为该基因型血清学阴性。
结果 在3组牛中的2组以及新大陆骆驼科动物组中鉴定出抗BPI3V抗体血清学阳性的动物。在所有3组中，针对BPI3V - B的几何平均抗体效价显著高于针对BPI3V - A和BPI3V - C的效价。所有山羊、圈养白尾鹿以及第三组牛群中的牛对该病毒的所有3种基因型均为血清学阴性。
结论及临床意义 结果表明，BPI3V - A可能不再是阿拉巴马州有蹄类动物中流行的主要基因型。这可能具有临床相关性，因为BPI3V经常参与牛呼吸道疾病综合征的发病机制，目前的疫苗仅包含针对BPI3V - A的抗原，并且针对各种BPI3V基因型的抗体之间的交叉保护程度尚不清楚。
